I'm doing a intergration with our inhouse engine,we use virualstudio.and we found houdini engine only have .a to link.bad new. it 's a hard work to deal with that. why not just give us a lib,so we can make our life eazier. thanks

Did you mean Visual Studio? If so the libHAPI library works with VS 2012.

I have been using this lib file with Houdini 14 and VS 2012.

It's purely a naming different but otherwise the .a files are really just .lib files. If you just set libHAPI.a as your link library, everything should work.